Polar organic compounds in the river Elbe — Development of optimized concentration methods using substance-specific detection techniques

Different methods for solid phase extraction (SPE) of polar, organic compounds found in Elbe water were compared. Mass-spectrometric detection (MS) after liquid chromatographic separation (LC) or flow injection analysis (FIA) and thermospray ionization (TSP) was used to assess the concentration behaviour as well as the detection techniques. A selected compound was identified using tandem mass spectrometry (MS/MS) carrying out mixture analysis.     

Determination of organic sulphur compounds in sediments of the river Elbe using gas chromatography with flame photometric detection

Sediment samples from different reference sites representing typical situations on the river Elbe were analyzed for organo-sulphur compounds (OSC). Gas chromatography with sulphur specific flame-photometric detection was used for the identification and quantification of individual OSC. Chromatographic retention data for 42 standard heterocycles were determined and compared with the composition of sediment extracts. An extraction scheme used for the OSC determination is described. Dibenzothiophene (DBT), its alkylated homologues, phenanthro[4,5-bcd]thiophene, benzo[b]naphtho[2,1-d]thiophene and in some cases still unidentified compounds were the predominant OSC. Depending on sampling site and date the qualitative composition of sulphur heterocycles detected by the described method varied, and the total concentrations of all OSC ranged from 0.3 to 21 mg/kg.     

Mass spectrometric investigations of water extracts of the river Elbe for the determination of potential inputs of pollutants into the North Sea

A non-target screening by gas chromatography-mass spectrometry has been carried out on water extracts of the river Elbe in order to obtain an overview of organic compounds being dissolved or bound to suspended matter in the Elbe. Samples of 1001 volume were taken at the freshwater border at Stade and extracted by liquid-liquid extraction with pentane. Before GC-MS analysis, the water extracts were fractionated into 15 subsamples by HPLC on an SiO₂ column. A sensitivity of ca. 50 to 250 pg/l was reached for the GC-MC analysis. Several hundreds of natural and anthropogenic compounds could be identified or at least grouped into a compound class. The presence of a number of compounds could be verified from earlier investigations, in addition a great number of anthropogenic compounds were described which have previously not been reported for the river Elbe.     

Transformations of mercury species in the presence of Elbe river bacteria

The influence of Elbe river bacteria isolated from suspended particulate matter (SPM) on dynamic species transformation of mercury was investigated. Experiments were carried out in the presence of bacteria (batch cultures) and in sterile tapwater as a control. For the methylation of inorganic mercury ions by bacteria several cofactors are under discussion. In this work, methylcobalamin, methyl iodide and S-adenosylmethionine were tested as biogenic methyl donors and trimethyl-lead chloride, trimethyltin chloride and dimethylarsenic acid as abiotic methyl donors. Transmethylation reactions as examples of abiotic methyl transfers have higher effectiveness in the formation of methylmercury (CH₃Hg⁺) than methylation with biogenic compounds. This result was observed in batch cultures as well as in sterile water. SPM-bacteria inhibit methyl transfer to mercury(II) ions. This is not only due to passive adsorption processes of mercury(II) to bacterial cell walls; methylmercury is also decomposed very rapidly by SPM-bacteria and is immobilized as mercury(II) by the cells.     

Monitoring of priority pesticides and other organic pollutants in river water from portugal by gas chromatography-mass spectrometry and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry

Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS) were optimized and applied for the trace-level determination of 42 priority pesticides and 33 priority organic pollutants from European Union Directive EC 76/464. First, off-line solid-phase extraction of 200 ml of river water using an OASIS solid-phase extraction cartridge, followed by GC-MS was used. Next, selected samples that were positive to GC-MS were analyzed by LC-APCI-MS in order to detect further polar byproducts or to improve the determination of previously detected polar analytes. The transformation products of triazine pesticides like deethylatrazine (DEA) and deisopropylatrazine (DIA) and compounds such as diuron and several chlorophenols were positively identified by LC-APCI-MS. The present methodology has also been used for searching for new analytes not included in the EC 76/464 list, like Irgarol, DEA and DIA. In addition it was applied to target pollutants in 43 river water samples from Portugal during a pilot survey from April to July 1999. Atrazine followed by simazine and 2,4,6-trichlorophenol were the most ubiquitous compounds detected in this area. The levels detected of the different compounds were in the range of: 0.01-2.73 microg/l, 0.05-0.74 microg/l, 0.02-1.65 microg/l, 0.02-5.43 microg/l, 0.01-0.40 microg/l, 0.01-0.26 microg/l, 0.02-0.61 microg/l, 0.01-3.90 microg/l, 0.01-1.24 microg/l, 0.02-2.3 microg/l, 0.01-0.13 microg/l and 0.01-0.5 microg/l for atrazine, simazine, terbuthylazine, alachlor, metolachlor, Irgarol, propanil; tributhylphosphate, diuron, 2,4,6-trichlorophenol, deisopropylatrazine and deethylatrazine, respectively.     

Input of hydrocarbons into the North Sea by the river Elbe

An analytical procedure for evaluating the conditional stability constants K of aluminum/humic substance complexes, based on ²⁷Al nuclear magnetic resonance spectroscopy, is described. It is well suited for the determination of Al(III) dissociated from dissolved humic substances at slightly acidic pH values. The new procedure offers a good sensitivity and requires neither special preparation of the sample nor the evaluation of complex coupled chemical equilibria. The pK values range from 2.0 to 4.3 depending on the ratio [Al_complex] to dissolved organic carbon and the pH.Dedicated to Professor Dr. Dieter Klockow on the occasion of his 60th birthday     

Advances in the determination of volatile organic solvents and other organic pollutants by gas chromatography with thermal desorption sampling and injection

Summary The problem of the separation of 34 volatile organic chlorinated compounds is solved by using three different GC columns selected according to the needs of the particular separation required. The effect of water vapor contained as moisture in the trapped air on the retention of some characteristic compounds is studied. The influence of dead volumes on trap injection is also studied.Dedicated to Prof. Dr. A. Liberti on the occasion of his 70th birthday.     

Pesticides and other chemical contaminants

A new topic needs to be added to this refereeship this year. This topic is Ultra-trace method for pesticides in bottled soft drinks. The Study Director is Paul Milne. The topic Dioxins by GC/MS remains vacant.     

Organotins: their analysis and assessment in the Elbe river system, Northern Germany

Organotins have been analyzed using a new derivatisation technique in wet sediments by ethylation with NaBEt₄ and a GC/AAS coupling for separation and detection. In this way the Sn(IV) and the monoalkylated compounds could also be analysed more easily than by the Grignard derivatisation method used by other authors. Organotins are present not only as expected in the harbours, shipyards and the pleasure boat areas but also in the river itself, upstream of these places. Ships are thus not the only sources. An organotin production plant on the banks of a tributary, the Mulde river, is characterised by high tetrabutyltin and lower tributyltin amounts along the river to its mouth over 350 km away. The concentrations are up to 14 mg tetrabutyltin (Sn)/kg sediment. The superimposed patterns are from ship antifouling paints, characterised by a high content of tributylin in different stages of degradation to di and monoalkylated compounds; this shows the bacterial degradation possibilities for organotins in the river. In general, organometallics are a contaminant of great concern in the Elbe river system.     

Monitoring of total Hg in the river Elbe: FIA-device for on-line digestion

The development of an apparatus for the on-line sampling, digestion and quantification of total mercury in surface water is described. Detection and quantification is done by flow injection cold vapor atomic absorption spectroscopy (FI-CVAAS). Three digestion methods were tested, chemical, microwave and UV. The influence of the digestion parameters (digestion method, digestion time, microwave power, concentration of oxidation solution) on the recovery of mercury in water of the river Elbe have been investigated. Mercury can be determined almost quantitatively (recovery rate > 85%) with some digestion procedures described. The best results were reached by UV digestion. The technique is fast, simple to handle and robust. Each complete analysis only take four minutes. The working range is 10 to 1000 ng/L. The measuring arrangement has been applied successfully in a governmental monitoring station at Schnackenburg/Elbe, Germany.     

Monitoring of total Hg in the river Elbe: FIA-device for on-line digestion

The development of an apparatus for the on-line sampling, digestion and quantification of total mercury in surface water is described. Detection and quantification is done by flow injection cold vapor atomic absorption spectroscopy (FI-CVAAS). Three digestion methods were tested, chemical, microwave and UV. The influence of the digestion parameters (digestion method, digestion time, microwave power, concentration of oxidation solution) on the recovery of mercury in water of the river Elbe have been investigated. Mercury can be determined almost quantitatively (recovery rate > 85%) with some digestion procedures described. The best results were reached by UV digestion. The technique is fast, simple ¶to handle and robust. Each complete analysis only take four minutes. The working range is 10 to 1000 ng/L. The measuring arrangement has been applied successfully in a governmental monitoring station at Schnackenburg/Elbe, Germany.     

Determination of aromatic sulfonates in the river Elbe by on-line ion-pair extraction and ion-pair chromatography

An automated method based on ion-pair extraction and HPLC has been used to investigate the occurrence of aromatic sulfonates in the river Elbe. Twelve different naphthalene, anthraquinone and stilbene sulfonates have been found. The substances have been detected by UV detection at 220 nm and, if possible, by their fluorescence signal. The aromatic sulfonates have been identified by their retention time and by comparing their UV spectra with the respective spectra of reference substances. The occurrence of these substances in the river Elbe water is caused by a discharge of several waste water effluents. The results showed, that certain naphthalene sulfonates cannot be totally removed by biological treatment and adsorption on activated carbon.     

Improvement, quality assurance and analytical results on the river Elbe contamination in the Czech Republic

Environmental analysis at trace levels is a new field of research in the Czech Republic since about ten years. New methods have to be adapted, pollution sources have to be investigated and quality assurance has to be established. The improvement in the detemination of trace substances in the Elbe river, mainly that of organic pollutants, is shown. A first insight on an international level is given into the origin of pollution in the Czech part of the Elbe river and the analytical work provided by the Czech water research institute and one of the most important monitoring laboratories.     

Preconcentration of gaseous organic pollutants in the atmosphere

Three basic methods of preconcentration of organic atmospheric pollutants, viz. by cold trap, absorption in solutions and adsorption on solids at ambient temperature, and methods of liberating the trapped components, are discussed. Adsorption on solids is becoming more widely employed because of its advantages, and selection of the most appropriate sorbent for a given group of pollutants is of major importance. The characteristics of individual types of sorbents are presented, as well as the basic methods of determination of sorption capacity.     

On-line determination of mercury in river water at the German monitoring station Schnackenburg/Elbe

A monitor is described which provides the on-line determination of mercury in river water at concentrations from 20 to 1000 ng/L. The measurement includes an on-line digestion with Br-/BrO3- and UV-radiation. Each determination is controlled by an on-line addition of 50 and 100 ng/L mercury carried out by pre-dilution of a 500 and 1000 ng/L stock solution using sequential injection analysis (SIA). One cycle of analysis takes 20 min and results in nine signals. A five days stand-alone operation has been performed successfully. Details are also published at web page: "http/www.rzbd.fh-hamburg.de/-prmercol".     

On-line determination of mercury in river water at the German monitoring station Schnackenburg/Elbe

A monitor is described which provides the on-line determination of mercury in river water at concentrations from 20 to 1000 ng/L. The measurement includes an on-line digestion with Br^–/BrO₃ ^– and UV-radiation. Each determination is controlled by an on-line addition of 50 and 100 ng/L mercury carried out by pre-dilution of a 500 and 1000 ng/L stock solution using sequential injection analysis (SIA). One cycle of analysis takes 20 min and results in nine signals. A five days stand-alone operation has been performed successfully. Details are also published at web page: “http/www.rzbd.fh-hamburg.de/¶～prmercol”     

State-of-the-art in organic elemental micro and ultramicro analysis

Summary Nernst developed a quartz torsion microbalance in 1903. In consequence of this pioneering work, Emich in the Technical University of Graz, Austria, had systematized a series of chemical operations in microscale as well as a microchemical analysis. Further advances in technique and method of organic microanalysis had been accomplished by Pregl in Graz in 1912. His work had been strongly supported by a new microbalance which was known as Kuhlmann microbalance. Pregl's original methods of analysis were arranged and published in 1916 as Die quantitative organische Mikroanalyse. It is still noteable that the Nobel prize of 1933 had been presented to Dr. Pregl. In accordance with a combination of electronic microbalance and computer techniques, organic elemental microanalysis has grown to include advanced instrumentation and on-line computation. Successful adaptation of microchemical analysis has expanded today not only to pure organic compounds, but on industrial intermediates, polymers, food additives and many other compositions. The paper includes a discussion of the relative merits of traditional and modern analytical techniques together with the progression of microbalances. Recent developments in organic micro and ultramicro analysis in Japan are also described.